Conventionally, during execution on a game screen, because synchronization between a screen output by a display adapter and a frequency of display sweep is not achieved, a situation of a broken or torn screen often occurs, which causes a user to be affected when the user is viewing a game screen. Therefore, some display adapter manufacturers develop a vertical synchronization function (V-Sync). By means of the V-Sync, a frequency of a display screen update is reduced, so as to achieve synchronization with a frequency of a display adapter update. However, under the architecture of an existing display panel, if a frequency of a display screen update changes, when a user views a display screen, the user would find the problem of inconsistent screen brightness.